1. Field of the Invention
The present invention relates to a copying machine and, more specifically, to a copying machine capable of copying in a manual feeding mode in which sheets of copy paper are manually fed, and in a so-called 2 in 1 mode in which images of two originals continuously fed are copied on a single sheet of copy paper.
2. Description of the Related Art
A copying machine in which the 2 in 1 mode can be set having an automatic document feeder (hereinafter referred to as an ADF) has been proposed.
In the 2 in 1 mode, two originals are continuously fed by using the ADF and they are arranged next to each other on a platen, with the images of the originals are read and copied on a former half and the latter half of a single sheet of copy paper.
Now, when a sheet of copy paper is divided into two by a line orthogonal to the paper feeding direction of the sheet of copy paper, an area on which the images are first formed will be referred as to the former half while the area in which the images are formed thereafter is referred as the latter half.
Meanwhile, a copying machine has been provided which has manual paper feeding means and capable of manually feeding sheets of copy paper.
The manual paper feeding means comprises a dedicated paper feeding inlet (manual paper feeding inlet) and a manual feed tray which can be arranged to guide the sheets of paper to the paper feeding inlet.
A manual feeding mode to carry out the copying operation by manual paper feeding is set when the above mentioned manual feeding tray is set in an available state (namely, a state in which the sheet of copy paper can be guided to the manual paper feed inlet), for instance.
The maximum width of the sheet of copy paper which can be manually fed is equal to the maximum width of possible image formation by the copying machine, in general. The maximum length of the sheet is equal to the maximum length of the possible image formation of the copying machine. In other words, if the size of the sheet of copy paper is in the above range, manual paper feeding is possible.
In this specification, the direction of setting the originals are defined as a breadthwise direction (in which the direction of feeding the original corresponds to the short side, as shown in FIG. 4A) and a lengthwise direction (in which the direction of feeding the original corresponds to the long side, as shown in FIG. 4B), and the directions of setting the sheet of copy paper are also defined in the same manner.
With the directions of setting the originals and the sheets of copy paper defined as described above, the 2 in 1 mode can be defined as a mode in which images of two originals continuously fed in the breadthwise direction are copied in composition in the former and the latter half of a sheet of copy paper fed in the lengthwise direction.
Therefore, in the 2 in 1 mode, the relation between the original size and the size of the copy of paper, and the relation between the set direction of the original and the set direction of the copy paper must be determined, and the sizes, the directions of setting and the copying magnification rate, if necessary, must be appropriately set accordingly.
The above described setting process is carried out by a CPU of the copying machine on the promise that the original and the sheet of copy paper are both of regular sizes. The size of the original and the size of the sheet of paper must be detected before the start of paper feeding operation.
However, the size of the sheet of copy paper which is manually fed cannot be detected before the start of paper feeding, as the sheet of copy paper is out of the copying machine, as described above. In addition, a sheet of copy paper having an irregular size may be fed.
Therefore, when the copying operation is carried out in the 2 in 1 mode by manual paper feeding, miscopies such as missing of images may be generated.